This picture, Tiepolo's largest and most dazzling oil sketch, represents Apollo about to embark on his daily course across the sky. Deities around the sun god symbolize the planets, and allegorical figures on the cornice represent the four continents. Tiepolo presented this preliminary sketch to Carl Philipp von Greiffenklau, the prince-bishop of Würzburg, on April 20, 1752, as his proposal for the decoration of the vast staircase ceiling of the Residenz, often considered the artist's greatest achievement.

From December 1750 to November 1753, Tiepolo was employed in Würzburg by Prince-Bishop Carl Philipp von Greiffenclau to decorate his magnificent palace, the Residenz, designed by Balthasar Neumann. The artist's first commission was to fresco the banqueting room, the Kaisersaal. This work is the modello for Tiepolo's decoration of the ceiling above the grand staircase, for which he received the formal commission in July 1752. Earlier decorative programs divided the vault of the stairway into separate fields treating historical subjects. The revised program, inspired by the succession of Greiffenclau as prince-bishop in 1749 and his decision to engage Tiepolo to decorate the Residenz, abandoned history in favor of a more conventional allegory lauding the prince-bishop as Apollo, the god of light and patron of the arts, illuminating—both literally and figuratively—the four corners of the earth.

Tiepolo's composition centers on the figure of Apollo as he prepares to make his daily journey across the heavens (see Additional Images). In front of and below him butterfly-winged Hours (Horae) present his horses and reins, and putti push his heavy gold chariot up a bank of clouds. Around him are grouped the Olympian gods who govern the planets. Most prominent are Venus and Mars, who repose on a dark cloud. Rotating 180 degrees, we have Mercury, his right hand pointing toward Apollo's horses as he announces the beginning of another day to Jupiter. Around the cornice are grouped depictions of the four continents. Figures at the four corners are painted in monochrome, to be created in stucco by Antonio Bossi, Tiepolo's collaborator, along with his son Giandomenico, on the project.

The most important difference between the modello and the ceiling is the transposition of the continents of Europe and America. The result of this change is that rather than initiating the visitor's experience as she does in the modello, in the fresco Europe has become its climax, heightened by the addition of an oval portrait of Greiffenclau held aloft by Fame and Glory (or Virtue). Another change from the modello to the fresco is that in the former the light source is imagined as emanating from Apollo rather than from the various windows in the stairwell. These and the many other changes, including a number of a secco revisions, underscore Tiepolo's restless genius and illuminate the fact that even a modello of this size and complexity documents only a stage in a constantly evolving process: a process that took place within the established limits of traditional fresco practice and balanced artistic license with iconographic models. Clearly, the modello had a dual function. If, on the one hand, it proposed an iconographic scheme, on the other, it served as an independent demonstration of Tiepolo's fantasy and artistic brilliance.

Edward T. Evans. The History and Topography of the Parish of Hendon, Middlesex. London, 1890, pp. 239–40, notes that there is a painted ceiling in a lobby off the hall at Hendon Hall, and identifies the subject as the four quarters of the globe; states that all the paintings "are said to have been inserted by the direction of [David] Garrick himself".

"Tiepolo Discovery: Painting on Hotel Ceiling." Times (March 31, 1954), p. 5, ill. (detail), notes that the picture mentioned in Evans's "History of Hendon" (1890) was recognized by a Mr. J. B. Gold as a study by Tiepolo for the Würzburg painting of Olympus and the four continents; believes that the Hendon Hall work was a study for the ceiling, rather than a later variant or version of the composition, since it differs in a number of details from the large painting; reports that Mr. Gold believes the picture was acquired and put up by Brian Scotney who bought the house after Mrs. Garrick's death in 1822.

Illustrated London News (April 10, 1954), p. 559, ill., mentions it as a new find.

Antonio Morassi. G. B. Tiepolo: His Life and Work. London, 1955, p. 25, fig. 35, ascribes it to Giovanni Battista Tiepolo, dates it 1752, and calls it a modello for the staircase at Würzburg; titles it "Olympus, the Quarters of the Globe, and other Allegories".

Antonio Morassi. "Some 'Modelli' and other Unpublished Works by Tiepolo." Burlington Magazine 97 (January 1955), p. 4 n. 1, identifies it as a modello by Giovanni Battista Tiepolo for the staircase at Würzburg (1752), newly discovered at the Hendon Hall Hotel, London.

F. J. B. W[atson]. "Giovanni Battista Tiepolo: A Masterpiece and a Book." Connoisseur 136 (November 1955), p. 215, describes it as a sketch, either for or after the ceiling, noting that even if it is a later record it could be by Giovanni Battista Tiepolo.

Antonio Morassi. Letter. April 24, 1956, confirms the attribution to Giovanni Battista Tiepolo, regarding it as the preparatory sketch that Tiepolo presented to the prince-bishop in April 1752.

George Knox. "Tiepolo: Die Fresken der Würzburger Residenz." Burlington Magazine 99 (April 1957), p. 129, rejects the attribution to Giovanni Battista Tiepolo on the grounds that the painting's proportions differ from those of the Würzburg ceiling, the groups of Europe and America are reversed, and it is "too 'artistic,' too finished and too detailed"; accepts, however, the thesis that this picture was the one presented by Tiepolo to the prince-bishop on April 20, 1752, but claims that "the chore of preparing such a work may well have been entrusted to Domenico".

Fritz Neugass. "Sommerlicher Ausklang in New York." Weltkunst 30 (August 15, 1960), p. 6, mentions it as a preliminary study by Tiepolo for the Würzburg fresco.

Jack Gold. Letter to Mrs. Wrightsman. November 12, 1961, as "obviously painted before the ceiling, not afterwards as a record"; considers the picture more likely to have been brought to Hendon Hall not by Garrick, but by a later owner, Ware.

Antonio Morassi. A Complete Catalogue of the Paintings of G. B. Tiepolo. London, 1962, pp. 37, 68, calls it one of the most splendid large modelli by Tiepolo.

"Review of J. Byam Shaw, 'The Drawings of Domenico Tiepolo,' London, 1962." Times Literary Supplement (August 31, 1962), p. 652, attributes it to Domenico and calls it "demonstrably not a preparation for the finished ceiling but done after it".

Francis Watson. "G. B. Tiepolo: Pioneer of Modernism." Apollo 77 (March 1963), pp. 247–48, argues that it was made as a record of the Würzburg ceiling by Domenico Tiepolo, because it is painted on a red bole ground and because the proportions of the figures in relation to the overall dimensions of the composition differ from those of the ceiling fresco; suggests tentatively that a series of Domenico's red chalk drawings after the frescoes were "actually produced with the idea of such a modelletto in mind".

Gerhard Bott. "Zur Ikonographie des Treppenfreskos von Giovanni Battista Tiepolo in der Würzburger Residenz." Anzeiger des Germanischen Nationalmuseums (1965), pp. 140–64, fig. 2, considers it an autograph work by Giovanni Battista Tiepolo, very likely the sketch that was presented to the prince-bishop on April 20, 1752; discusses the iconography of the fresco.

Claus Virch. "Dreams of Heaven and Earth: Giambattista and Domenico Tiepolo in the Wrightsman Collection." Apollo 90 (September 1969), pp. 173–74, 176–78, fig. 3, attributes it to Giambattista, rejecting the notion that it could have been made by Domenico.

Francis Watson. Letter to Everett Fahy. April 15, 1970, concludes that it was painted after the ceiling, as a modello would certainly have made reference to Greiffenklau or the prince-bishop, its program being the glorification of the house of Greiffenklau; comments that it is "by no means certain that the picture was painted immediately after the execution of the ceiling".

Dr. Fritz Nathan und Dr. Peter Nathan, 1922–1972. Zürich, 1972, unpaginated, no. 19, ill., illustrate it as one of the pictures sold by the Nathan firm.

Everett Fahy inThe Wrightsman Collection. Vol. 5, Paintings, Drawings. [New York], 1973, pp. 232–47, no. 25, ill. p. 233 (color), figs. 1–9 (details), catalogues it as Giovanni Battista Tiepolo's sketch for the staircase ceiling at Würzburg, possibly identical to the one presented to the prince-bishop on April 20, 1752; notes that the iconographical scheme is similar to the ceiling of the Palazzo Clerici, which Tiepolo had decorated less than two decades earlier; suggests that Tiepolo's design could also have been inspired by the large fresco by Johann Rudolf Byss over the staircase of the Schönborn Castle at Pommersfelden, which was located only a few miles from Würzburg; points out that the most significant difference in composition between the fresco and the oil painting is that the latter does not show the prince-bishop or his retinue.

Mark Ashton. "Allegory, Fact, and Meaning in Giambattista Tiepolo's Four Continents in Würzburg." Art Bulletin 60 (March 1978), p. 121, fig. 16, notes that Tiepolo had to shift the various deities in order to introduce the prince-bishop's portrait above Europe (his home continent) in the final fresco, and that this therefore "cancels any suspicion that the planetary deities have important iconographic links to the earth".

Svetlana Alpers and Michael Baxandall. Tiepolo and the Pictorial Intelligence. New Haven, 1994, pp. 74, 129–30, 135, 142, colorpls. 144, 146, 151a–c (overall and details), note that the artist expands the original material into the fresco in three main ways: lateralizing, stretching, and splitting.

Stéphane Loire and José de Los Llanos inGiambattista Tiepolo, 1696–1770. Exh. cat., Musée du Petit Palais. Paris, 1998, p. 230 n. 12, under no. 76, compare the placement of the figure of Apollo in the MMA picture with that of the figures of Spain and Hercules in "Wealth and Benefits of the Spanish Monarchy under Charles III" (National Gallery of Art, Washington).